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Fire Protection Panel (Cockpit Panel) (Sheet 1 of 2) Dornier 328Jet - Fire Protection Page 1

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Fire Protection Panel (Cockpit Panel) (Sheet 1 of 2)

Dornier 328Jet - Fire Protection

Page 1

Fire Protection Panel (Cockpit Panel) (Sheet 2 of 2)

Dornier 328Jet - Fire Protection

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CARG FIRE (red)– Illuminates during fire test loop and when actual cargo compartment

fire occurs.

Red Warning Panel

Dornier 328Jet - Fire Protection

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Engine Fire Extinguishing Sequence

Dornier 328Jet - Fire Protection

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APU Fire Extinguishing Sequence

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APU Fire Protection Panel (Ground Control Panel)

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MESSAGE (SYNOPTIC) WARN INHIBITLocation (COLOR) TONE CONDITION

1 2 3

SMOKE CARGO FAIL Cargo smoke detector failed.

CAS Field (AMBER)

SMOKE LAV Smoke in lavatory.

CAS Field (AMBER)

SMOKE LAV FAIL Lavatory smoke detector failed.

CAS Field (AMBER)

Message inhibit logic: 1. WOW, Engines off and Electrical Bus Failure refer to Section 12–27–032. Takeoff phase3. Landing phase

CAS Field and System Messages

Dornier 328Jet - Fire Protection

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FIRE PROTECTION AND OVERHEAT DETECTION

GENERALFire protection, consisting of fire detection, warning and extinguishing, is provided by threeindependent systems: one for the LH/RH engines each and one for the auxiliary power unit(APU). Each system includes electrical fire detection and extinguishing circuits, cooperating withwarning, arming and discharge button lights. Two fire extinguishing agent (Firex) bottles areinstalled for each engine in the rear compartment of the pylon, aft of the fire wall and outside theengine firezone. One bottle is installed for the APU in front of the forward fire wall of the APUcompartment outside the fire zone. An illuminated discharge (DIS) light indicates low pressurein the Firex bottles. Test switches test the electrical continuity of the detection and dischargecartridge circuits.

Each system is capable of detecting electrical short circuits in the sensing cable circuits. A loop(LOOP) fail light on the engine FIRE PROTECTION control panel (overhead panel) illuminatesto indicate a fire detection failure.

Titanium fire walls on the engine pylon and in the APU compartment serve to isolate the engineand APU fire zones from the adjacent airfoil structure. The fuel and engine bleed air lines can allbe isolated from the engine fire zones by shutoff valves located behind the fire wall and from theAPU fire zones on the inboard side of the fire wall.

Fire and overheat detection for the engines are provided by detection elements in each enginecompartment. The position of the detection elements are:

– the inner side of the left and right engine cowl doors– the engine turbine section

Fire and overheat detection for the APU is provided by detection elements in the APUcompartment. The position of the detection elements are:

– the area around the compartment structure– on the underside of the upper fire wall and on the forward fire wall.

FIREWIRE SENSOR CABLEHeat sensitive cables are routed through the fire and overheat detection zones and areconnected to fire/overheat detection units. Each firewire sensor cable is a co–axial electricalcable consisting of two conductors, a stainless steel outer conductor grounded to the airframeand an inner conductor connected in a closed loop to a control unit. The two conductors areseparated by a semi–conductor material which decreases in electrical resistance astemperature increases. When the resistance of the semi–conductor decreases to a preset limit,a warning is generated to the flight compartment. A single break in a cable does not impair itswarning capabilities but if a cable is broken in more than one place, any section between thebreaks will not function and the failure would be indicated by a loop fail light when the testswitch is selected to loop test.

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Engine and APU Firewire Sensor Cable – Installation

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FIRE/OVERHEAT CONTROL UNITSTwo engine fire/overheat control units and one APU fire/overheat control unit are installed belowthe cabin floor in the front part of the fuselage in a pressurized environment. The control unitsmonitor the LH/RH engine and APU fire protection and overheat detection system.

Each control unit contains two separate alarm circuits to discriminate between valid fire oroverheat warnings and fault indication generated by sensing cable short circuits. The unitscompare the speed and extent of sensing cable resistance change and initiate fire warningscaused by fire or overheating.

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FIRE PROTECTION SYSTEM COMPONENTS AND CONTROLSThree red fire warning buttons marked ENG LH FIRE PUSH, APU FIRE PUSH, and ENG RHFIRE PUSH, each guarded by a security cover, are located on the FIRE PROTECTION controlpanel on the overhead panel in the flight compartment.

If a valid fire warning is received, the control unit causes the appropriate fire warning button(s)to illuminate and activates the fire warning alert. The illuminated fire warning button(s) and theaural fire warning alert continue to operate as long as a fire/overheat condition exists.

The fire warning alert is silenced when one of the MASTER WARNING lights on the glareshieldpanel is pushed. If a fire control unit detects a short circuit signal, the appropriate amber LOOPFAIL light on the FIRE PROTECTION control panel comes on to indicate the failure.

FIRE WARNING CIRCUIT TESTINGThree TEST switches on the FIRE PROTECTION control panel are used to check theserviceability of the engine and APU fire detection warning and fault circuits.

Engine Fire Warning TestSetting the appropriate engine TEST switch to the upper position (FIRE SQUIB) causes thefollowing lights to illuminate:

– the MASTER WARNING lights,– the appropriate red FIRE lights on the red warning panel (RWP),– the appropriate red ENG FIRE button warning light(s) (loop test):

– fire detection loop is ok, no breaks detected (if the system has a short circuit, theappropriate LOOP FAIL light is already on, and the particular fire warning light remains off)

– the appropriate green SQUIB lights (BTL1/BTL2) (cartridge test):

– the cartridge of the particular extinguisher is okand

– the FIRE BELL in the flight compartment to sound.

Setting the appropriate engine TEST switch to the lower position (FAIL AGN) causes thefollowing lights to illuminate:

– the appropriate green AGN lights (extinguisher test):

– the required agent capacity of the particular extinguisher is available

– the appropriate amber LOOP FAIL light:

– the circuit of the control units in the fire loop is functional.

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APU Fire Warning TestSetting the APU TEST switch to the upper position (FIRE SQUIB) causes the following lights toilluminate:

– the MASTER WARNING lights,– the red APU FIRE light on the red warning panel (RWP),– the red APU FIRE button warning light on the FIRE PROTECTION control panel and APU

ground panel (loop test):

– fire detection loop is ok, no breaks detected (if the system has a short circuit, the LOOPFAIL light on the FIRE PROTECTION control panel is already on, and the APU firewarning light remains off)

– the green SQUIB light (BTL) in the flight compartment and on the APU ground panel(cartridge test):

– the cartridge of the extinguisher is okand

– the FIRE BELL in the flight compartment and

– the APU FIRE HORN on APU ground panel to sound.

NOTE: The APU fire shutoff relay is isolated from the fire warning circuits when the test isperformed. This permits operation of the APU during the fire warning system test.

Setting the APU TEST switch to the lower position (FAIL AGN) causes the following lights toilluminate:

– the green AGN lights (extinguisher test):

– the required agent capacity of the extinguisher is available

– the amber LOOP FAIL light:

– the circuit of the control unit in the fire loop is functional.

FAULT CASEIf a short circuit occurs in any one fire detection loop, the amber LOOP FAIL light illuminatesautomatically. A break in the loop will not be indicated, because the function of the system is notaffected. An interruption or break can only be detected by selecting the TEST switch to thelower position.

If there is low pressure in the extinguisher due to a leakage or no pressure due to a bottledischarge, the white DIS light will be illuminated automatically.

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FIRE/OVERHEAT CASEIf there is a fire or an overheat condition in anyone engine nacelle, there will be four separateindications in the flight compartment as follows:

– MASTER WARNING light illuminated– ENGINE LH/RH FIRE warning light on RWP– red LH/RH ENG buttons lights illuminated– fire warning alert (FIRE BELL) sounds.

If there is a fire or an overheat condition in the APU compartment, there will be four separateindications in the flight compartment as follows:

– MASTER WARNING light illuminated– red APU FIRE warning light on RWP– red APU FIRE button light illuminated– fire warning alert (FIRE BELL) sounds.

Additionally a dual indication will be on the APU ground panel as follows:

– red APU FIRE button light illuminated– fire warning alert (FIRE HORN) sounds.

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FIRE EXTINGUISHING

The fire extinguishing systems for the two engines and the APU are controlled by buttonslocated on the FIRE PROTECTION control panel on the overhead panel in the flightcompartment. Five Firex bottles are provided, two for each engine, and one Firex bottle for theAPU. Firex bottle low pressure warning lights and test switches for the bottle dischargecartridges (squibs) are integrated into the FIRE PROTECTION control panel and the APUground panel.

ENGINE FIRE EXTINGUISHING SYSTEM OPERATION

NOTE: The operation of the LH/RH engine fire extinguishing system are identical.

When a fire or overheat condition occurs in the detection zones of an engine, the appropriatefire/overheat control unit causes the red ENG FIRE button light to illuminate and the fire warningalert (FIRE BELL) to sound. Pushing the ENG FIRE button light arms both squibs of the engineFirex bottles and causes the green BTL 1/BTL2 SQUIB button to illuminate. In addition, thefollowing will occur:

– the fuel shutoff valve will be closed– the fuel motive flow valve will be closed– the bleed air shutoff valve will be closed– the AC generator will be switched off– the auto–ignition will be switched off

and– the DC generator will be switched off.

Pushing the green BTL 1 SQUIB button allows pressurized Firex agent to flow through theoutlet port and associated discharge lines into the fire zone of the left engine. As the Firex agentdischarges, the green BTL 1 SQUIB light extinguishes and the white BTL 1 DIS light illuminates.

If the fire condition persist after bottle 1 has been fully discharged, the green BTL 2 SQUIBbutton can be pushed to fire the squib on bottle 2. The Firex agent from bottle 2 is also releasedthrough the outlet port and associated discharge lines into the fire zone of the engine. As thepressure in bottle 2 decreases, the green BTL 2 SQUIB light extinguishes and the white BTL 2DIS light illuminates.

SYSTEM RESETAfter a fire warning occurs and the appropriate ENG FIRE button is pressed, the fire warningand extinguishing system can be reset, if circumstances warrant, by pushing the ENG FIREbutton a second time which returns the system to the pre–warning condition except for the fuelshutoff valve, the DC generator and the ECS bleed valve. These functions can only bereactivated by moving the thrust lever to the CUT OFF position and respectively recycling theGEN ALT and BLEED buttons.

WARNING: NEVER TRY TO RESTART AN ENGINE AFTER ACTUAL FIRE.

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APU FIRE EXTINGUISHING SYSTEM OPERATIONThe operation of the APU fire extinguishing system is similar to the operation of the LH/RHengine fire extinguishing system described above with the following exceptions:

NOTE: The APU Firex bottle discharges into the APU compartment.

Pushing the APU FIRE button light arms the squib of the APU Firex bottle and causes the greenBTL SQUIB button light to illuminate. In addition, the following will occur:

– the shutdown of the APU through the APU fire shutoff relay will be initiated– the bleed air shutoff valve will be closed– the fuel shutoff valves on the APU normal feed and negative–g protection lines will be closed

and– the APU DC generator will be switched off.

SYSTEM RESETAfter a fire warning occurs and the APU FIRE button is pressed, the APU fire warning andextinguishing system can be reset, if circumstances warrant, by pushing the APU FIRE buttona second time which returns the system to the pre–warning condition except for the fuel shutoffvalve, the APU DC generator and the APU bleed air valve. These functions can only bereactivated by recycling the APU MASTER button on the APU control panel OFF and ON andby pressing the START button to restart the APU.

WARNING: NEVER TRY TO RESTART AN APU AFTER ACTUAL FIRE.

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Engine and APU Fire Extinguisher System Discharge Lines – Installation

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SMOKE DETECTION AND FIRE EXTINGUISHING – LAVATORY

GENERAL

A smoke detection and an automatic fire extinguisher system is installed in the lavatory. In theevent of smoke being detected in the lavatory an amber message will appear on the EICAS.

If the ambient temperature in the lavatory exceeds a pre–determined limit the fire extinguishersystem will operate independent of crew action and a warning illuminates on the red warningpanel.

SMOKE DETECTION SYSTEM

An ionisation smoke detector with built–in test equipment (BITE) is fitted to roof of the lavatory.If smoke develops in the lavatory the detector senses the change in air density caused by thesmoke and will send an amber SMOKE LAV message to the CAS field of the EICAS.

If the detector or its associated circuitry fails a SMOKE LAV FAIL amber message on the CASfield on the EICAS comes on.

EXTINGUISHING SYSTEM

A fire extinguisher is fitted above the lavatory waste bin. The extinguisher comprises a pressureswitch and a discharge arm and nozzle. Incoporated in the discharge nozzle is a heat sensitivecapsule that in its passive mode prevents discharge.

If the ambient temperature reaches 780C the heat sensitive capsule melts and extinguishingagent discharge automatically. The pressure switch senses the loss of pressure in theextinguisher that results in a LAV FIRE message on the red warning panel and a triple chimewarning tone.

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Lavatory Smoke Detector and Fire Extinguishing System

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CARGO COMPARTMENT SMOKE DETECTION AND FIRE SUPPRESSION SYSTEM

GENERAL

An automatic smoke detection and manual activated fire extinguisher system for the cargocompartment is installed inside the pressurized fuselage shell.

The Cargo Fire Protection System (CFPS) indicates fire (latest one minute after ignition) andremains on for the duration of fire/smoke, indicates when the fire is extinguished (warningsOFF) and indicates reignition of fire.

The CFPS comprises following components:

– smoke detector (with heat detection device)– fire suppression bottle for high rate discharge– fire suppression bottle for metered discharge (metering device in the discharge head)– two nozzles in the cargo compartment– tubing / fittings– check valve / T–check valve– distribution box– cargo fire control panel in the cockpit.

RWP

Cargo FireControl Panel

DAU

EICAS

Distribution SmokeDetectorBox

Speaker

TCPS 1 TCPS 2

T–CheckValveCartrige Cartrige

Metering/Drying Device

CheckValve

Nozzles

High Rate Discharge Bottle Meterde Discharge Bottle

Alarm Pulse

Cargo Compartment Smoke Detection and Fire Extinguishing System Schematic

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SMOKE DETECTION SYSTEM

A photoelectric smoke detector with a built–in test equipment (BITE) is fitted to roof the of thecargo compartment measuring the presence of smoke particles in the air. The detectorcompensates for environmental influences and performs automatic re–adjustments of its smokealarm threshold settings caused by pollution.

An integrated temperature sensor compensates temperature influences and generates a firealarm above the temperature threshold of 85OC (inside temperature).

In case of smoke/fire or a fault detected by the BITE a signal is sent to the DAU and to theCargo Fire Extinguisher Panel.

The smoke detector is equipped with a test feature to be initiated through the Cargo Fire ControlPanel.

EXTINGUISHING SYSTEM

Two Halon fire extinguisher bottles are fitted beneath the floor panels of the cargo compartment,one with a high pressure discharge and the other one metered. Each extinguisher comprises acombination fill valve/safety relief valve, a temperature compensated pressure switch and adischarge outlet assembly with a cartridge. The extinguishing agent is led through pipes to twonozzles installed in the ceiling panel.

If the system is activated via crew initiated commands, the explosive cartridges (squibs) of bothbottles are ignited forcing a rupture disc incorporated in each discharge outlet assembly to burstand thus allowing the agent to discharge through the distribution pipes into the cargocompartment. The high–rate bottle discharges in less than 2 seconds and rises the Halonconcentration to 5% (volume) while the metered bottle discharges continuously to keep a Halonconcentration above 3% for at least 1 hour.

If an overpressurization condition in excess of the primary safety relief valve occurs, the rupturedisc assembly serves the dual function of being a mechanism for discharging the agent and thesystem‘s secondary safety device.

To monitor whether the fire suppression bottles are fully charged or not a temperaturecompensated pressure switch (TCPS) is mounted on the container. The TCPS closes a switchcontact when a small amount of pressure loss occurred at any ambient temperature. Pressuredifferences due to a temperature increase/decrease are compensated. A loss of pressure isindicated on the cargo fire control panel.

A check valve integrated in the tubing prevents water collection in the discharge line of the fireprotection system. The valve opens in flow direction and closes water tight in unpressurizedcondition.

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Component Installation / Location

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OPERATION

GeneralFor indication and operation of the fire protection system a cargo fire control panel is installedin the center pedestal of the cockpit. The control panel comprises a safety covered CARGOFIRE button, a DIS BOTTLE button, a secured TEST Switch and a DET FAIL indicator.

A warning light CARG FIRE is activated on the RED WARNING panel and an audio warningsignal is created by the audio warning system, to alert the crew of a possible fire in the cargocompartment.

Fire/Smoke ConditionIf a fire/smoke condition in the cargo compartment is detected the flight crew will be alerted byfollowing indications in the cockpit:

– TRIPLE CHIME on and MASTER WARNING (red) flashing– CARG FIRE warning light (red) on RWP illuminated– CARGO FIRE button (red) on the cargo fire control panel flashing

Pushing the CARGO FIRE button on the cargo fire control panel arms the system and the squiblights SQ1 and QS2 illuminate, indicating that the system is ready to discharge. To fire the bottledischarge cartridges (squibs) and allow the pressurized agent to dispense, the DIS BOTTLEbutton has to be pushed. As the detonators have fired and the pressure in the extinguisherbottles decrease, the green SQ1 and SQ2 lights extinguish and the white DIS (discharge) lightcomes on respectively. The red warnings remain on for duration of fire/smoke.

NOTE: The CARGO FIRE button is secured with protective device to prevent inadvertentactivation.

Fault IndicationsIf the smoke detector is inoperative or a wiring failure between the smoke detector and thedistribution box exists following indications are given to the flight crew:

– DET FAIL light (amber) on the cargo fire control panel illuminated– SMOKE CARGO FAIL caution message (amber) on the EICAS displayed– SINGLE CHIME on and MASTER CAUTION light (amber) flashing.

If there is a wiring failure between the power supply busses and the distribution box or cargo firecontrol panel following indications are given:

– SMOKE CARGO FAIL caution message (amber) on the EICAS displayed– SINGLE CHIME on and MASTER CAUTION light (amber) flashing.

If there is a loss of pressure (no fire) following indication is given:

– DIS BOTTLE button (white) on the cargo fire control panel illuminated.

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Test ModeThe condition of the smoke detector and the extinguisher bottles are tested (pre–flight–test) byusing the TEST switch on the cargo fire control panel. In TEST FIRE SQUIB position a testsequence for the smoke detector is initiated. In TEST FAIL AGN position a bottle check isperformed.

NOTE: The test switch cargo fire is secured with protective device to prevent inadvertentswitching.

NOTE: The test switch cargo fire has to be kept in TEST position for at least 10 seconds torelease the test sequence.

Setting the TEST switch to TEST FIRE SQUIB position causes the following indications:

– TRIPLE CHIME on and MASTER WARNING (red) flashing– CARG FIRE warning light (red) on RWP illuminated– CARGO FIRE button (red) on the cargo fire control panel flashing– DET FAIL light (amber) on the cargo fire control panel illuminated– SINGLE CHIME on and MASTER CAUTION (amber)– SMOKE CARGO FAIL caution message (amber) on the EICAS displayed– SQ1/SQ2 lights (green) on the cargo fire control panel illuminated.

Setting the test switch to TEST FAIL AGN position causes the following indications:

– AGN light (green) on fire control panel illuminated.

If the agent capacity is too low, the white DIS light is already on, and the AGN light on the firecontrol panel remains off.

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